自东精对 Acidity of Alkynes Terminal alkynes,R-C=C-H,are more acidic than other hydrocarbons. ■Acetylene-→acetylide by NH2,but not by OH-or RO-. More s character,so pair of electrons in anion is held more closely to the nucleus. Less charge separation,so more stable.Acidity of Alkynes ◼Terminal alkynes, R-CC-H, are more acidic than other hydrocarbons. ◼Acetylene → acetylide by NH2 - , but not by OH- or RO- . ◼More s character, so pair of electrons in anion is held more closely to the nucleus. Less charge separation, so more stable